1. Field of the Invention
This invention relates generally to computer systems, and more particularly provides a system and methods that provide for synchronizing information among two or more devices.
2. Background
The development of more capable and less expensive computing technologies is not only increasing the number of personal computer or “PC” users. It is also providing a broader variety and number of computing devices, and increasing the number of users utilizing more than one computing device (e.g. a PC, cell phone and PDA). It is observed, however, that techniques used with conventional computing devices and information may well become problematic with regard to emerging devices, device interconnection and information handling, as well as the number of users utilizing such emerging technologies.
Conventional synchronous data synchronization, for example, provides for completely synchronizing specified user data on two of the user's computing devices upon each application of a synchronization algorithm.
Prior to synchronization, specified user data residing on a first user device (“first device data”) is transferred to and stored at the network server (“server data”). Synchronization is then typically initiated upon a later startup or shutdown of the first user device, or periodically, according to user preferences.
During synchronization, the server completely synchronizes the server data with the first device data and with corresponding data residing on the second user device (“second device data”). That is, assuming no conflict exists, a copy of all identified modifications to the first device data is transferred to the server, and the server correspondingly replaces or adds to the server data; a copy of the modifications now made to the server data is then similarly made to the second device data, replacing or adding to the second device data as needed. If a conflict exists, i.e., a data element has been modified at both user devices, then the network server typically resolves the conflict by preferring one user device over the other, or by allowing the user to select one of the data versions. If the first device modification is selected, the server replaces the corresponding second device data. The server then similarly synchronizes any non-conflicting modifications to the second device data with the server data and then the first device data.
Despite its proliferation, however, conventional synchronization is also subject to certain disadvantages. For example, conducting each synchronization with regard to all of the specified data on even two of a user's devices can require substantial user device resources. This can become particularly problematic with less capable user devices, such as smart phones or PDAs, since a user may be denied use of his device throughout the synchronization process.
Synchronous synchronization can also require substantial network resources. For example, the network bandwidth required for synchronizing potentially large amounts of data for a increasing number of users may become unmanageable. Similarly, while apparently sufficient, a significant increase in the number of users seeking synchronization services may strain network server capabilities. In any event, those resources that might otherwise be available for other uses must instead be devoted to conducting synchronization.
Still further disadvantages include those relating to the availability of up-to-date information and security. For example, extended time requirements might prompt a user to conduct synchronization other than at startup (e.g., before using a cell phone) or on a less frequent periodic basis. A user might therefore end up using out-of-date data that is available and appears valid prior to synchronization. The maintaining of security might also become problematic, since authentication and any encryption of the entire dataset are typically conducted by the “more capable” network server of the synchronization service provider.
Accordingly, there is a need for a synchronization system and methods that enable computing device information to be synchronized while avoiding the disadvantages of existing synchronization.